Method of making curved wrought-metal pipe-fittings.



L. H. MHNKMAN.

METHOD OF MAKING OUBVBD WBOUGHT METAL PIPE FITTINGS.

AFPLIOATIOB' YILED JAHJS, 100B.

Mar. 29, 191%.

3 BHEBTB-BHEET 1.

\Afiui messes v I nue n% or Louis H.B1-i 9 L. d. BRINKMAN.

METHOD OI MAKING GUBVED WROUGHT METAL PIPE FITTINGS.

APPLAOJIJXUU FILED LAX. 12,1006.

Patented M11129, 1m.

6 L lntlei cqvgk cu s r1 mom B35 v orney 5 G S 0 S T 8 n j "Tu u W Q L. H. BRINKMAN. METHOD OF HAKING GUBVED WEOD'GET HETAL PIPE FITTINGS.

APPLIOATIOH FILED JLLI'. 12, 190B.

Patented Mar.29,1910.

3 SEESTQ-GEEET 3v {5? QB Inuenfow LOLL' Briglgm n W UNITED TATEE1 PATENT OFFICE.

LQDUIS H. BRINKMAN, F HARTFORD, CONNECTICUT, ABSIGNOEL T0 WHITLOCK COIL PIPE CGBIPANY, 6F NEST HARTFORD, CGNNECTICUT, .A. CORPORATION 013' GDNHECEKCU'EL.

METHOD OF MAKING WRUUGHT-METAL IIPE-FITTINGS'.

fi, Specification 012 Letters Patent.

Patented 19MB.

Lppllcuttou riled Janssir 12, 1806. Berle! L'Io. $165,710.

To all who-m ii may concern:

Be it known that 1, Louis II. Bniniumn,

a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented a new and useful improvement in Methods of Melting Cur -ed Wrought-Metal vPipe-Fittings, which the following is u specification, seconipunied by drawings forming a part of the same, in Which-- Figure 1 represents a straight piece of pipe from which my improved fitting is made. ,Fig. 2 illustrates the lilst step in the process of bending. Fig. 3 represents the bent pipe. Fig. 4 represents the process of cooling the convex side of the pipe completing the bending operation. Fig. 5 represents the pipe as bent by the operution illustr" ted in Fig. 4. Fig. 6 is sectionnl view of the bent pipe on line 6-6, liig. l igy. 7 a plan view of one of the comPiessing cies for restoring the contour of the pip" Fig. 8 is a side elevation of the eonipressi gdies. Figs. 9 and 10 illustrate the method of perfecting the cylindrical contour of the pipe throughout its bent section. Fig. ll illustrates the method of expunding the screw threaded flanges at the ends of the bent pipe. Fig. 2 represents completed pipe titling known as a return bend. Fig. 13 is a centr ll sectional vim-v of the completed fitting. Fig. 14 represeiics a: return bendhaving a curvature of less radius than that shown in Fig. 12, the radius of curvature at its bent section bein considerably less than the diunieter of tie pipe. Fig. 15 represents 2. pipe bent to t rni an elbow, and Fig. 16 reoresents n completed elbow. Fig. 17 is e view of a inonitied bending apparatus. Fig}. 18 is n sectioned view of a return bend. Fig. is a sectional view of the holding dies and W s. 20 and 21 represent a completed ri return *nd.

Similar reference letters mid figures refer to similar parts in the different; views.

My present invention relates to 2i new and improved plrocess of making curved Jipe fittings, sue for example, elbows an re- 'n hnds of wrought inetgzl, M-.. the object my invention is to increase the strength, decrease weight, and reduce the expense of this class of fittings which at at resent, formed oi cast inctnl, nnd it consists in shaping the pipe fittings from Wrought metal as hereinafter described and pointed out in the annexed claims.

In carrying my present invention into practice I first cut from a wrought metal pipe of the requisite diameter, either of iron or steel, s piece of suitable length to form the desired tilting, said piece heir-.w represented at 1, Fig. 1. I next best tile piece of pipe 1 and hand it at its central section to form an obtuse angle as represented at 2, Fig. the operation of bending being carried out by any suitable uppsratns, such, for example, as that represented in plan view in Fig. 2, in which the piece of pipe 1 is held with its center bearing against-n roll 3 and its opposite side neaner its fixed end esting against a roll 4. Opposite to the "ll 3 as a water pipe 4 by means of which n Of cooling water is directed against the convex side of the bending pipe. A bending strein is exerted upon the ipe l by the rotstion of the roll 5 around t is roll 3, and the free end of the pipe is bent into the position shown by the broken lines 6. The pipe bent, as shown at 2, Fig. 3, is then placed against the fixed rolls 7 and 8 and P. reciprociitixw former is moved in the rection of the arrow id to crowd the pip): between the rolls 7 and 8 and cause it to bent around the ferrite: & into the U-sliape, shown at 11,.in Fig. 5.

Previous to, during the btlidli'ti operiition illustrated in Fig. 4., the been or convex side of the pine 2 is cooled by a spray of water directed against the pipe by a water ipe 12 provided with minute roles nrrang to direct a multi licitp1 of streems u ,einst the convex side 0 the eated pipe, said water pipe being ifnrnished from source 01' water supply through is flexible pipe 13.

The operation of bending the pipe into 2. ti-shape shown in Fig. 5, tends to contract the pipe on the line M, Fig. 5, milking the cross section of the pipe on line 6-6, less than the normal diameter of the pipe before bending, snd'at the some time to increase the diameter of the pipe on the broken line 141 i, Fig. 6. This shape or the 1P0. is a. result of applying the entire (infective bendin strain to the oonenve side of the bend. accomplish this the diiference "J in teiiipersiture oetwwn th two sides of the pipe at the bending point, for, as the convex the object of compressing the pipe side is cool and the conceive side hot, the bending strain will compress as shown in Figs. 6 and 18, the inside of t e bend which is in a more or less plastic condition before the oi the outside of the bend are stretched in er wor the pipe is bent you the cool outside as a fulcrum and all e distortion of the pipe will occur upon the inside of the bend. The wall of the pipe therefore, whatever the radius of the end, will not he made thinner b stretching upon the convex side of the d, but the only result will be to thicken the wall of the pipe upon the inside of the bend. It only remains then to restore the original circular shape and diameter to the inside of the pi at the bend by reforming the wall of t e Dips at the concave side of the bend, while the pipe is still plasti see Figs. 13 and 21. ll accomplish this asollowszbent as shown in Fig. is compresse between :2. of dies 15 and 16, said dies provided with a recess 17 which is circular no crosssection throughout its entire end having a diameter equal to the outsi diameter of the bent pipe. Owing to. the contraction at its bent section, a space 18 will be left between the hat portion of the ipe and the side 19 of the in the ies, and between the dies 15 and 16 is to restore the cylindrical form of the pipe at its bent section by com ression between the dies which reduces e diameter on line 1414:, Fi 6 and expands the of the pipe pipe laterally to fill the. space 18, thereby restoring the circular contour of the pipe, as shown at 20, Figsv 9 and 10. After the circular contour of pipe has been restored compression b the dies 16 and 16, l next force as of balls through the pi as shown in Figs. 9

and 10 by e U-shspcd pipe 20 in a recess 21 t drm die plaice 22 and 28 said die plates hevin longitudinal chan- 24and25inwhi first,aball26is placed as shown in Fig. 9, whose diameter to the interior diameter of the pipe. The ilot hall 26 is followed icy series of tl smaller hells 27 which pushed forw by a follower 28, causing the pilot ball 2% to he forced through the ipe 20 into the position shown at 8, Fin.

As the than the pilot ilot bell arrives at 6 Fig. 10, the bent pipe can be withdrawn an the smaller halls removed.

27 are slightfi; ball 26, as soon as the cats die plates, one of which is shown at 29, Fig. 11, provided with enlarged recesses at the of the pipe to form annular spaces so around end of the pipe. The ends 81 of the pi e are then expanded by means of dies 82 Wish ere force... into the of streiwii -01 cost the position shown The bent pipe 20 18 then held between a pair of dupliceases thd ipe, themhy trending it to fill the annu ar space 30 an for-min on each end of the p: the expanded anges 83, as shown in 12 end 13. The flanges 33 are then provide-d with internal screw threads 34 and the return bend is completed.

In the manufacture of elbows the straight piece of pipe can be bent sulhciently at a sini le operation, such as that illustrated in lg. 2 to form the desired curvature for the elbow, as shown at 35, Fig. 15, and the ends of the elbow are then expanded to form flanges 36, 36, to receive an internal screw thread, as shown in Fig l6.

I am aware that wrought metal pipe has heretofore been bent and returned u n itself by a curvature of 180, thus formin in the pipe 8. return bond which is a part 0 and integral with the pipe itself. This method of bending pipe has been possible where the radius of curvature Wes largely in excess oil the diameter of the pipe. An attempt to hand a WXOUfihl metal ipe upon a small radius, Such, fin examp e, as one approximately the diameter of the pipe or less, not only reduces a crimping of'the concave side a? the bent pipe due to the process upeettin but it also stntches the outer convex nice of the bent' pi and redraw its thereby weakening the 101 my. improved process I chic to ben pipe upon a curvaturemf very radius or less than the diameter of the i and I also prevent the mtchingp l e outer or convex side of the t pipe, thereby preserving the original thickness and strength of the i Return bends end elbows constructed my improved process can he manufacture at the cost selected tiell of cast metal fittings, and they ere much lighter in weight, as well as stronger, and as the flanges teeter tensile stre th the liability of cheifiting or splitting e flanges in applying the fittings to pipe, which is a common defect of cast metal fittings, is thereby avoided. It is sometimes sought increase the tensile fittings by forming the ttings of or malleable iron, which not only adds to the ex of the fittings, but renders liah e todist rtion of their in the process of an- By my method of ex ending the they are rendered ebso utely cylindrical and concentric with the pipe.

So far as I am aware, wrought metal tittings of iron or steel, manufactured from straight icces of pi ing, are an entirely new arti e of menu acture -in the art of pip?l fittings.

Fig. 14 I have shown a completed return bond 35 hsvin the radius of its curvature less than the iameter of the ipe, and in the manufacture of 2; return ban of such small radius, the abruptness of the bend not only tends to stretch the convex side of the pipe and deer-use its strength, but it. also tends to crimp the concave side of the pi )e by upsetting. producing wrinkles in t to pipe. 'lbese de cots are counteracted by my method of makiir.

in Fig. 17 it iave shown a. method of bending a return bend at one operation by the use of a sliding former 3'1, and a pair of nuindrels 38, 38, held by plates 39, 39, which are capable of swinging about axes indicated b the broken lines 40, 40. The cooling of t 1e pipe is accomplished by water jets which are supplied through pipes 41, 41, having flattened nozzles 42 42.

The s c'tioual view in Big. 18 shows the ettect upon the metal caused by the bending and cooiinfl' of the outer or convex side. As shown in Fig. 18, the normal thickness of the pine is maintained at its outer or convex sit c at &3, while the entire strain upon the )ipc results in thiclw mg or upsetting of t to inner or concave side of the pipe at H. The section shown in Fig. 18 represents the condition of the bent ipc. after it has been compressed between the dies 15 and it; but before the pilot ball 26 has been forced throu h the pi e, which restores the interior diameter of the pipe. The action of the ball 26 in its passage through the pipe expands the inner or conceive side A for the reason that the outer or convex is held against the dies as shown at -15, Fi it while the space 46 between the dies and the inner or concave side of the pipe and in addition, the outer side of the pipe has been ttttu-iiitl to resist expansion, while the inner or concave side is still hot and ductile.

Fig. 20 shows a return bend 47 which is not provided with the expanded flanges 33, Fig. 13, but has its ends Welded to the ends of pipes 48, 48. The longitudinal compression of the welded ends exterior rib or annular rejection 'li'he welding may be eccomp ished by electricity or other convenient method.

Fig. 21 shows in sectional view the return bend 47 having its ends welded to the pipes 48, 48, having its interior diameter testored to the normal diameter of the pipe before bending, and with the excess of metal crowded into the concave side of the bend prodnci a thickening of the pipe,- as at 44. \Vhat claim as my invention and desire to sectmc by letters Patent is i. The within described method bending pipe, comprising hosting to be neat, exerting n bending strain upon said pipe, and cooliu \1/ the outer or convex side of the bend during the application of the bending strain.

2. The within described method of bend lttg iohlofitfiiflpilflmg sp iying a bending side of the bend cooler than the inner or concave side of the bend. wberebv the pipe on the inner side of the bend will be upset by the bendiiu strain before the iipe on the outer side of t 1e bend is stretcheil.

23. The within described method of bending straight pieces of pipe, comprising cooling the pipe during tie bending n'ocess on the convex or outer side of the nd sufticiently below the tctu erature the concave or inner side of the bend so that the pi e on said concave side may be compressed without elongation of said convex side by the bending strain.

4. The within described method of bending pipe, comprising up lying a bending strain to a pipe, with sat pi )e on the convex side of the bend sullicicut y cooler than on the concave side of the bend so that the bending streil fill thicken said concave side without chs ing said convex side, then restoring the circular contour and original diameter the bent section of the pi the within described method of iiending pipe, comprising uppl inw a bending stniin to a piece of pipe 0 w riltllil. the side forming the inner'or concave bend st a higher temperature than the outer or convex bend so that the shape of said pipe will '2, distorted by the bending strain upon said inner or concave bend before the cont/c? or outer bend is stretched, and restoring the bonding process distorted inner or We bend to its oriczinai shape and diunset ti. 'lllie within describedniethod of bending a nece of metal pipe, comprising exerting a bending strain upon the heated pipe, cooling during the bending rocess the convex or outer side of the hen and restoring the interior of the bent section of the pipe to its or ginal circular contour.

l in described method o bendpipc, comprising piece of pi; e, exerting a bending strain upon the heated portion and at the some time costing the convex or outer side of the bending pipe, whereby the interior or concave side of the pipe is upset and the outer or convex side is not disturbed by the bending process, and restoring the interior of the plpe to its original circular contour.

8. The method of making curved wrought metal pipe fittings, comprising heating a piece oi: pipe, bending the pipe to Eon-in an obtuse sag e, cooling the or convex surface or the. pipe, continuing the bonding to form a U-sha piece, compressing the bent section between dies having recesses corresponding to the normal outer diameter of the ipe, and forcing a ball through the bent pipe, having a diameter equal to the normal inner diameter the pipe.

9. The within described method of makstiain to pipe, with t e outer or convex: i ing curved pipe fittings consisting in heat"- Eli l l 23 g n sirmght p120; x

e of the desired g, bending the "use angle, c001- diznmivr of the heated piece to fol 311g ihc outer or convex p 021 of ihe bent sectiml, bending to & U-SZ. 3e, conmressing '1 V bent section to wstore 21c circular 01m suztiozz Fpmnding interior prev. 23 pipe to f 10. The 'iifizin described mg I w s, vslsmg strum upon a marked pxpe, applying; a

liquid 0 The Outer 0a" convex side of im; the hand during; a bending movesaq, whcmby 15 only the inner or concawebend of said plpc will be disaforied by the bendinw a restoring after the bending torted cnncuve side of iihe circuiur contour. 

